Category Archives: Uncategorized

Virtualization Technologies for Education on Computer Networking and Research

Mitko Shopov

Abstract: The use of virtualized platforms is a cost effective and affordable solution. Virtualized environment offers high flexibility in laboratory experiment design as topology changes can be made by software changes. The high scalability and flexibility of virtual networking enables design of large scale, complex, and advanced networking experiments and laboratory exercises that would not be built otherwise using physical equipment. The paper presents the use of virtual networking technologies along with GNS3 tool in the education and research on computer networking in DSNET virtual laboratory, part of Technical University of Sofia, branch Plovdiv.
Key words: Computer Networking, GNS3, Qemu, Virtualization, VMWare

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Evaluation of the Routing Algorithms with Reduced Energy Consumption

Ile Dimitrievski, Valentin Molloy

Abstract: This paper presents an evaluation of a special routing algorithm with energy reduced consumption in comparison to one without any energy consumption optimization. We apply Noxim discrete event simulator specialized for simulation of Network on Chip (No C) architectures. Evaluation is made over a 7×7 2D mesh structure which is the most used model nowadays. Comparison between the popular state-of-the-art XY routing algorithm and DyAD one is given, as well. DyAD routing algorithm for NoC combines the advantages of both deterministic and adaptive routing algorithms. Calculations on the above algorithms are performed by means of the Noxim simulator with examples on 2D mesh topology.

Key words: Adaptive, deterministic, DyAD, Network on Chip, power consumption, random selection, routing algorithms, 2D mesh topology.

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A Model of Hybrid Ontology for Medical Information

Mariya Evtimova, Ivan Momtchev

Abstract: It is proposed a model of hybrid ontology that is case based, but is also suitable for big data as it is implemented rules. This ontology is divided into three parts- crisp part, fuzzy and probability part and big data part. Ontology use theory of the fuzzy sets with addition of probability logic for the realization of the fuzzy and probability part of the ontology. This hybrid ontology is suitable for vague and uncertain reasoning as it improve the quality of the returned results. Quality of the returned results is very important in the medical domain.

Key words: Big data, Case based reasoning, Fuzzy logic, Ontology, Probability logic

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A Hybrid Technique for Kidneys Segmentation from Axial CT Images

Elena Kalcheva-Yovkova, Technical University, Sofia

Abstract: This paper represents some results of a hybrid technique for kidney segmentation from axial computed tomographic images. The proposed technique combines edge based, region based and morphological watershed based algorithms with prior anatomical knowledge of the human abdomen. It includes kidney region extraction, coarse watershed based segmentation and adaptive refinement. The approach is tested on several CT datasets in DlCOM standard. The results of the segmentation of the left and right kidneys are quantitatively assessed using supervised evaluation technique including similarity, consistency and distance measures. The average values of specificity, sensitivity and accuracy are relatively high (above 0,96) and mean value of Dice coefficient is about 0, 95. The global consistency error values alter between 0,02 and 0,05 and the average Hausdorff distance is around 0,06.

Keywords: Computerized tomography images, contrast enhancement, morphological gradient, watershed segmentation, supervised evaluation.

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Comparison and Applications of Geolocation Services in Mobile and Web Platforms

Antoniya Tasheva

Abstract: The paper examines the contemporary services for finding user’s location in different applications. The main methods for finding the geolocation are described and their accuracy, speed and resource consumption are compared. Examples for geolocation usage are presented. Possible security issues are marked with their solutions.

Key words: Geolocation, Location, HTML5, GPS

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An Overview of ICT Platforms Designed for Cognitive Rehabilitation of Neurological Patients

Galidiya Petrova

Abstract: This paper presents an overview of ICT platforms and systems designed for cognitive rehabilitation of neurological patients with working memory deficits and disruption of executive functions. The main aim is to analyze their main characteristics and differences and to identify their possible applications for personalized and continuous rehabilitation at home setting. The possibility to train patients with more complex tasks is also taken into consideration.

Keywords: lCT platforms, cognitive rehabilitation, neurological patients.

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Examining Resource Sharing in Social Networks and Learning Management Systems

Adelina Aleksieva-Petrova, Plamen Tenev

Abstract: This research presents a platform which benefits from Social Network Sites (SNS) sites and Learning Management Systems (LMS). The platform offers resources semantically to its users based on their interests and relations. In order to provide these recommendations, the model provides elements for representing the content through the use of an ontological model. This model is further enhanced with semantic techniques for the characterization and relationships between user profiles, resources and social networks. In fact, with this model could be the basis of recommendation system based on social media data, and it could be exploited use by the recommendations on different products, which are stored in the Web and with similar characteristics between them.

Key words: clusterization, LMS, social networks, SNS, semantic data

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A Brief Survey of Segmentation Techniques Applied in Kidney Ultrasound Images

Stephan Vassilev

Abstract: The paper briefly explains research, domain and application related to the techniques applied in Kidney Ultrasound images. The first two sections introduce the domain area (ultrasound images and kidney problems related to them), the specific targets and formulate the problem. The rest two sections highlight the technologies and algorithms applied up to now, compare them and provide observations from that comparison. The paper also outlines some of the problems that can occur in different phases of the ultrasound kidney images.

Key words: Kidney, Ultrasound images, medical images, segmentation, models, graph, edge

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MVC Framework Approach in the Online assisted platform for Computer-aided Design in Communications — Online-CADCOM

Ognyan Chikov, Galia Marinova

Abstract: The paper presents the MVC Framework approach, implemented for the development of the platform Online-CADCOM. MVC programming approach is an architectural pattern that separates a web application into three main logical components: the Model, the View and the Controller, thus overcoming issues, rising from the complexity of web-based multitool design platforms. The architecture of the web application Online-CADCOM is described and it’s illustrated by the “View” section from the MVC Framework model.

Key words: Computer-aided design in communications, MVC Framework, Programming Layers, File Separation Content Management System

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Influence of Parameters of the Satellite Radio Channel on the Reception Quality of TV Signals

Lyubomir Laskov, Lidia Jordanova, Veska Georgieva

Abstract: In this paper an algorithm for design of the radio channel for satellite TV systems of first and second generation is presented. The algorithm allows taking into account the parameters of the repeater, satellite radio line and receiver, as well as the methods used for channel coding and modulation. The results of the research on the impact of ERP, the channel bandwidth, intensity of the rainfall, the size of the receiving antenna, noise ratio of LNC, earth position of the receiving antenna and others on the carrier to noise ratio on the receiver input are presented.

Key words: CNR, DVB-S, DVB-S2, E1RP, Satellite Channel

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